Dual-space Adaptive Synchronization Control of Cable-driven Parallel Robots

The main challenge of cable-driven parallel robots (CDPRs) stems from the motion control in which cables should keep in tension and coordinate each other during motion. Moreover, the uncertain model parameters also should be considered due to their influences on the motion control to some extent. To solve the above problems, a novel dual-space adaptive synchronization control (DASC) scheme is proposed to combine the adaptive synchronization in the cable length space with the adaptive compensation in the workspace. In the DASC scheme, the cable synchronization error is presented to represent the coordination motion relation among cables, and a dual-space adaptive method is then developed to compensate for the uncertain model parameters in different spaces in real time. The stability of the closed-loop system with the DASC scheme is proved strictly. The experimental results indicate that, compared with the traditional augmented PD (APD) control scheme, the DASC scheme can greatly improve the tracking accuracy of cables and the coordination relation among cables, and eventually increase the control accuracy of the mobile platform. Meanwhile, the adaptive effect in the DASC scheme can effectively compensate for the impact of the mass change of the terminal mobile platform.